You can export all your Data from Mastodon in the settings "Export" function (it's your data after all). I was genuinely surprised, that my archive is already 597 MB and that I have have 3235 posts here already 馃槉
I'm currently working on a desktop app, to display the contents of a Mastodon export (KDE-Frameworks based) to have a neat little viewer for it. Not sure ojn the name (yet)
I'll soon enable auto-delete for my data, so it's removed after 90 days.
